Electron tube



Jan. 6, 1942. 2E. ZINKE 2,269,073

ELECTRON TUBE Filed March 29, 1940 Patented Jan. 6, 1942 ELECTRON TUBE Erhard Zinke, Berlin, Germany, assignor to C. Lorenz Aktiengesellschaft, Berlin-Tempelhof, Germany, a company Application March 29, 1940, Serial No. 326,609 In Germany March 18, 1939 4 Claims.

This invention relates to electron tubes of the kind known as knob-type or acorn tubes, which have been constructed with a view to avoiding detrimentalcapacities and self-inductances due to the leading-in conductors or leads. The leads,

' sealed into the wall of these tubes, are located in the direction of radii and in a plane common to them. This wall is of vitreous or high-grade ceramic material. These materials cause diffi- 1 culties to arise when sealing the leads into them.

These difficulties are the greater the thicker the leads. The leads must therefore be of small cross-sectional area. As a result their strength is but small.

The invention aims to prevent injury to the leads and also provides for guiding the electron tube in a suitable holder. Another object is to decrease dielectric losses occurring between the leads of tubes having a base member attached to the portion of the tube from which the leads project.

The main feature of devices as provided by the invention is a supporting member, such as an insulating disc, which is fixed to the bulb of the electron tube and calculated to support the bulb when this is laid down on a plane surface, such as a table or the like. In this way the leads are protected from coming against such surface.

This and other features and advantages of the invention will be understood from the following description, reference being had to the accompanying drawing, in which Fig. 1 is a somewhat diagrammatic and partially sectioned view showing one embodiment of I the invention, Fig. 2 is a plan view of this em- By means of part 2 the discharge vessel is seated in an insulating disc 3. A handle 5 is screwed into the disc 3 and hence can be removed at will. Disc 3 has projections 6 arranged to engage with grooves of a holder 1.

Owing to these grooves and projections the assembly I, 2, 3, 4 cannot be inserted in the holder 1 until it is in the proper position with respect to this, that is, the position in which the leads 4 will be connected with the proper contact springs of the holder. These springs are not shown.

The body 3 may be provided with grooves instead of projections 6, the holder 1 in such case being fitted with ribs adapted for engagement with these grooves.

The dotted lines in Fig. 1 show that in geometrical relation the leads 4 are located within a cone whose surface is tangential to bulb l and disc 3, and that therefore the leads will not come against any plane surface, such as that of a table, on which the bulb may be laid down for any reason.

What is claimed is:

1. An electron tube having a bulb of a predetermined length, a disc-shaped member of insulation material attached to a portion of said bulb, and electrode leads projecting in radial directions from the wall of said bulb at a portion different from the portion of said bulb to which said member is attached, all of said leads terminating within a cone whose surface is tangential to the circumference of said member and the other end of said bulb.

2. An electron tube according to claim 1, wherein said leads are arranged in a plane which is nearer to one end of the bulb than to the other so that the bulb has a part shorter than the other part thereof, and said disc-shaped member is fixed to this shorter part.

3. An electron tube according to claim 1, further comprising a projection on the circumference of said disc-shaped member.

4. An electron tube according to claim 1 further comprising a groove on the circumference of said disc-shaped member.

ERHARD ZINKE. 

